stave off

When you stave something off, you prevent it from happening. When you stave off a cold, you work to avoid getting one, maybe by drinking plenty of tea and eating oranges.

You might help stave off the closing of a library by donating money and writing letters to the city council, or stave off the winter blues by traveling to a Caribbean island for a week. The phrase to stave off has a long history, dating from 1620 when it was used to mean "fend off with a staff," the way you might stave off a pack of growling dogs.